Designing an integrated circuit (IC) involves comprehensive self-testing. Such self-testing becomes more important for ICs having optoelectronic integration. The optical receiver should be tested electrically before being integrated with the photo diode (PD). Previous techniques of electrically testing an optical receiver only allow for adjustment of the data eye opening. Such techniques do not allow emulation of the effect of different photo diode capacitance and/or the effect of changing the optical transmitter laser power.